1- Select a subitem affected by inheritance,  and delete a parent link (right click : remove parent link -- or use the properties pane... hopefully these 2 will have the same effect, exactly)

 

2- the sub-item will keep its inheritance with the now defunct parent (ie : even if it has nothing to do with the previously inherited field anymore).

 

One could argue that it should keep it. Yes, that's why that the option can be set to "not" delete on item move... ;)